Non-Hospital Urgent and Emergency Care Units were created to deliver care to patients in chronic or acute situations and to coordinate the flow of urgent care. This descriptive study analyzed the theoretical knowledge of nurses working in these units concerning cardiopulmonary arrest and resuscitation. A questionnaire was applied to 73 nurses from 16 units in seven cities in the region of Campinas, SP, Brazil. The respondents displayed some gaps in their knowledge such as how to detect Cardiopulmonary Arrest (CPA), the ability to list the sequence of basic life support, and how to determine the appropriate compression to ventilation ratio (>60%). They also did not know: the immediate procedures to take after CPA detection (>70%); the rhythm pattern present in a CPA (>80%); and they only partially identified (100%) the medication used in cardiopulmonary resuscitation. The average score on a scale from zero to ten was 5.2 (± 1.4). The nurses presented partial knowledge of the guidelines available in the literature.